happymonday
09-10-2021, 03:46 AM
I installed 034 HFC - which triggered post cat P0420
Bought CTS turbo O2 spacer and fitted on post cat o2 sensor - which triggered P2196 lean code on pre-cat sensor
Was told that two sensors don't interrelate and that P2196 must have been a vacuum leak or problem with injectors.
I suspected that this was wrong.
Cleaned MAF, tightened exhaust and checked HFC bolts. rReplaced pre-cat o2 sensor. Couldn't find a leak. Didn't suspect a vacuum leak. I also changed injector seals and did it properly, so ruled this out.
I kept getting P2196 after a hundred or so miles, sometimes less. Checked forum after forum after forum. Everyone said vacuum leak, but it just didn't add up.
I found a random forum where a guy had posted that the CTS O2 spacer could be the issue.He said that if the post cat o2 sensor doesn't receive enough gases, then it can cause increased fuelling, which triggers the lean code P2196. That didn't make sense based upon what I'd been told.
But I thought, fuck it, I'll try it and bought a £11.50 (for a pair) of straight O2 spacers off Amazon to test his theory.
2PCS M18x1.5 O2 Oxygen Sensor Extender Bung Extension Adapter 45mm CEL Fix Kit.
https://www.amazon.co.uk/gp/product/B07QWRRY56/ref=ppx_yo_dt_b_asin_title_o08_s00?ie=UTF8&psc=1
Installed the spacer on post cat sensor. No codes. At all. For over 2000 miles now. No P0420 and no P2196. No issues. Problem solved. For the equivalent of £5.75
Moral of the story is that the two sensor readings must be compared against each other by the ECU, otherwise it wouldn't make any difference to P2196. Also that expensive CTS O2 spacers are a waste of money. You only need a cheap one, at least I only needed a cheap one.
Hopefully this helps someone else out.
Bought CTS turbo O2 spacer and fitted on post cat o2 sensor - which triggered P2196 lean code on pre-cat sensor
Was told that two sensors don't interrelate and that P2196 must have been a vacuum leak or problem with injectors.
I suspected that this was wrong.
Cleaned MAF, tightened exhaust and checked HFC bolts. rReplaced pre-cat o2 sensor. Couldn't find a leak. Didn't suspect a vacuum leak. I also changed injector seals and did it properly, so ruled this out.
I kept getting P2196 after a hundred or so miles, sometimes less. Checked forum after forum after forum. Everyone said vacuum leak, but it just didn't add up.
I found a random forum where a guy had posted that the CTS O2 spacer could be the issue.He said that if the post cat o2 sensor doesn't receive enough gases, then it can cause increased fuelling, which triggers the lean code P2196. That didn't make sense based upon what I'd been told.
But I thought, fuck it, I'll try it and bought a £11.50 (for a pair) of straight O2 spacers off Amazon to test his theory.
2PCS M18x1.5 O2 Oxygen Sensor Extender Bung Extension Adapter 45mm CEL Fix Kit.
https://www.amazon.co.uk/gp/product/B07QWRRY56/ref=ppx_yo_dt_b_asin_title_o08_s00?ie=UTF8&psc=1
Installed the spacer on post cat sensor. No codes. At all. For over 2000 miles now. No P0420 and no P2196. No issues. Problem solved. For the equivalent of £5.75
Moral of the story is that the two sensor readings must be compared against each other by the ECU, otherwise it wouldn't make any difference to P2196. Also that expensive CTS O2 spacers are a waste of money. You only need a cheap one, at least I only needed a cheap one.
Hopefully this helps someone else out.